Jaw grinding mechanism for car wheel boring mills



Jan. 4, 1949. H. IRWIN i 2,458,472

JAW GRINDI'NG MECHANISM FOR CAR WHEEL BORING MILLS Filed May 24, 1945 '3 Sheets-Sheetl J'Yrzvefzzdr Healy ITW/in.

H` IRWIN Jan.` 4, 1949.

' JAw GRINDING MECHANISM PoR CAR WHEEL BORING MILLS Filed May 24, 1.945

s sheets-she'et 2 -y I l l H. IRWIN Jan. 4, 1949. 2,458,472

JAW GRINDING MECHANISM FOR CAR WHEEL BORING'MILLS Filed May 24, '1945 3 Shee-ts-Sheet 3 Innen/0T.' He@ vIrwin.

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gripped by the-jaws for"holding"them in true`4 circular position while they are being ground.

This holding ring 5, as shown in Figs. 1 and 2, is"

at and is positioned to be engaged by thejaws below the wheel gripping faces 3 `thereof,.so``as not to interfere with the grinding operation. A plurality of spacer blocks 6 are provided and distributed around the table for supportingthe holding ring in proper level position. Both the holding ring and the blocks 6 are, of course, removed when the jaw grinding operation is completed.

the screw is provided with a hand crank 24 by which it may be conveniently rotated.

The motor grinding unit is mounted upon a sub-base consisting of the two parts 25 and 26 which are slidably connected for relative longitudinal movement for the purposes of further adjustment of the motor grinding unit. i As shown in Figs. 2 and 3, members 25 and 26 have a beveled groove and tongue connection 21 which provides The chuck jaws in a kboring machine yof this type are subjected to hard usage and are frequently damaged, particularly the gripping faces thereof. It becomes necessary, therefore, from time to time, to re-grind them in order to restore' tally disposed main supporting arm C upon which the motor driven grinding unit `D is mountedzand upon which also is mounted the grinding wheel dressing attachment E. The' whole mechanism is carried bythis arm which is arranged to be mounted upon the vertical boring bar B 'of the boring machine and thereby held in fixed position with respect to jaws to be ground.

This supporting arm has an enlarged end portion I0 somewhat elongated vertically and forms part II of a clamping member. The other partr of the clamp is formed by the cap member I3, both of these clamp members being clamped upon the boring bar by theboltsild. Both of these clamp members are provided with Vhalf 'round grooves which embrace the boring bar. In prac-` tice, the grooves can be made to t a boring bar of a given size, and if the machine is to be used.

on boring bars of smaller size shims can be used. The carrying arm is so "formed-as shown in the drawings, that it is offset from the axis of theor undercut groove or 'channel I'IWhich is engaged by correspondingly beveled ribs I8 formed on the face of the varm to provide an interlocked sliding connection between'the carriage and the arm. AThe carriage also has a lugIS which extends into a lengthwise groove 2U' in the arm. An adjusting screw 2I extends through this lug I S in threaded connection therewith and along the groove of the arm and provides means for shifting the carriage in either direction for .ad-

justment purposes. VThis4 adjustment screw is mounted in bearings22 and 23 at the inner and outer ends of the arm. The outer end of an .interlocked sliding connection between the vtwo parts. Member 25 has an extension 28 having a bearing 29 at its end for an adjustment screw 30, and this screw has threaded connection through the end portion of theI base member 26. A'hand'crank 3| is provided on the outer end of the screw forthe purposes of conveniently operating the screw to shift the motor.

'Thesub-base is mounted upon the carriage for rotary movement in order to provide angular adjustment `of the grinding unit with respect to the faces of the chuck jaws. The face of the carriage I6 has a circular pad 32 whichforms a flat bearing for a similar pad 33 on the sub-base member 26, and it alsofhas outstanding therefrom a center pin 34 which extends into a bearing in the base member 26 of the motor unit, as shown more clearly in Figs. 1 and 3, thus the motor unit may be rotatably adjusted about the center pin 34 for: positioning the grinding wheel at different angles with respect to the chuck jaw faces, as indicated in dotted lines in Fig. 1. A set screw 35 extends through the base member 26 into engagement with the center pin 34 by which the unit may be fastened or locked in any position to which it is rotatably adjusted. The flat bearing pads'325and 33 are of the same diameter and their peripheries are marked with calibrations 31, Fig. 3, for indicating the angular adjustment of the grinding Wheel.

The motorl grinding unit itself comprises a suitable powerrnotor 36 having a grinding wheel I5 at one end. In the present structure, the motor is of air driven type having the grinding wheel mounted at one end on its shaft and having at thepo'pposite end of its housing a handle or grip 38 by which it may be conveniently handled in moving it to its different adjusted positions. This motor unit is secured to its base member 25 by means of the clamps 39 which embrace the motor housing at two points. These clamps have wing nuts 40 operating on the clamping bolts 4I so that the motor unit can be conveniently mounted in place or removed therefromas desired.

When the jaws of the boring mill are to be faced or ground, the jaw holding ring is placed in position and the jaws arev closed against the ring. The main supporting arm C of the grinding mechanism is mounted on the boring bar B, ashereinbefore described, the grinding mechanism being thus held in a xed position against movement or rotation. The motor driven grinding wheel is then shifted to grinding position with respect to the jaws by means of its Various adjustments on the main arm C, and the table A is rotated by its own driving means to bring the jaws successively into grinding position so that all the jaws will be ground alike and in true, accurate, concentric and level relation to the boring mill whereby they will hold the car wheel in exact relation to the center'boring operations. The grinding wheel dressing attachmentE is mounted upon the'main supporting arm C and comprises in general a bracket and a cutting tool holder detachably mounted upon a post amish?! on the upper sideof the arm C. VThe post has a flange 4'6 atitslower end which is fastened ,to .amari-M von the` armcbv means of -zthe screws 48. The bracket comprises twoparts orfrnembers 45 and 50. The member 50 `has a sleeve 5I through which the post'45 extends.' `This provides a vertical adjustment for the jbracket to position the' cutting tool relatively to. the wheel f-tcrA be idressed. This sleeve 5I of.thewhracketisflocked inits-adjustedposition on the-:post by .means :Qf

-aiset screw 52 which extends through the .all'of the f sleeve` and into engagementA with the post 45. The postfhas a Ikeyway or tslot-=f513 which is .iengaged by the inner end of the set screw to lock the bracket against rotation. The bracket member 49 is pivotally connected with the bracket member 50 so that the dressing tool can be swung upwardly out of the way while the grinding unit is in operation.

As shown in Figs. 4 and 5, the bracket member 49 is divided or split at one end and receives between these divisions the portion 55 of the bracket member 50. A pivot bolt 51 extends through the divisions 55 and the portion 55, and is provided with a suitable clamping nut 58 on its threaded end to clamp the parts of the bracket in any position to which the bracket member 49 is adjusted. The outer end of the bracket member 4-9 has a sleeve 59 in which the shank 60 of the tool holder 6I is both rotatable and axially adjustable. The tool holder shank 60 has a lengthwise slot or keyway 62 and is provided with collars 63 having set screws 64 which engage the keyway. These collars bear against the ends of the sleeve and hold the tool holder against longitudinal movement, but they may be adjusted on the shank 60 to position the dressing tool in exact relation to the grinding wheel. A set screw 65 is provided in the sleeve for engagement with the slot in the tool holder shank for the purpose of locking the shank against rotation. The tool holder 6I has a suitable bore in which the cutting tool 65 is mounted. The parts are thus all adjustable and are arranged to be locked in their adjustable positions to present the cutting tool in exactly the proper position with respect to the grinding wheel. In Fig. 6 the cutting tool is shown as positioned to dress the grinding wheel with a nat grinding face. If, however, it is desired to form the grinding face of the wheel as a curve 61, as indicated in dotted lines in Fig. 7, the set screw 65 is loosened so that the tool holder can be rotated about the axis of its shank and by rotating the cutting tool transversely of the grinding wheel I5, as indicated in dotted lines in Fig. 7, the wheel can be given a curved or grooved grinding face.

In order to position the grinding wheel with respect to the dressing attachment, the grinding unit is rst rotated on its pivot 34 until its axis is in horizontal position on the arm C and the wheel is in a vertical plane. The unit is then shifted lengthwise of the arm C until its peripheral face is presented to the dressing tool. If the face of the wheel is to be dressed nat, as shown in Fig. 6, the carriage I6 can be traversed to move the wheel on a straight line with respect to the cutting tool. If, on the other hand, the wheel is to be given a curved or grooved grinding face, the wheel may be held stationary and the cutting tool rotated on the axis of the tool holder shank, as shown in Fig. 7.

It is desirable to Acheck the accuracy of the gauge ring 4 for ccncentricity yand level from time to time. For this purpose, I provide an arm dlhdetachablymountedon the ricain: arm-@C and extending in-1the1oppositedirection. arm serves-Jas :a support i'YfQr-.a'depending adjustable -L-.shapei d .f 'I I `onthe end .or which L,a suitable gauge 'L2 pivotally mounted. The gauge can thusfbegpositionedto contact the'several faces of the gauge ringwhileV it is Aclamped in the vjaws :and rotated bythe V boringmill table.

The combination of a 'boringmill @having .a vertical fboringbar land va rotary chuck .having a-,fs'eries of :radially movablecla-rnping jawsfa holding'ringadapted to hold the jaws. inl concentric relation to the axis of theboringbar, a jaw; l:grinclingffdevice adapted to be detachably mounted on said boring bar and adapted to grind the gripping faces of the jaws as the jaws are successively brought into grinding relation thereto by the rotation of the chuck, said grinding device comprising a main supporting arm having means at one endv for clamping the arm upon the boring bar, a grinding unit comprising a motor having a grinding wheel on its shaft, said grinding unit being mounted upon said arm with the axis of its shaft in a plane radial to the axis of the boring bar, and means for rotatably and bodily shifting the grinding unit in the plane of its axis to position the grinding wheel in grinding relation to the jaws.

2. The combination of a boring mill having a vertical boring bar and a rotary chuck having a series of radially movable clamping jaws, a holding ring adapted to hold the jaws in concentric relation to the axis of the boring bar, a jaw grinding device adapted to be detachably mounted on said boring bar and adapted to grind the gripping faces of the jaws as the jaws are successively brought into grinding relation thereto by the rotation of the chuck, said grinding device comprising a main supporting arm having means at one end for clamping the arm upon the boring bar, a grinding unit comprising a motor having a grinding wheel on its shaft, said grinding unit being mounted upon said arm with the axis of its shaft in a plane radial to the axis of the boring bar, means for rotatably and'bodily shifting the grinding unit in the plane of its axis to position the grinding wheel in grinding relation to the jaws, said monuting comprising a carriage shiftable lengthwise cf said supporting arm, and a sub-carriage rotatably mounted on said carriage in a vertical plane and having a member shiftable lengthwise of itself and carrying said motor grinding unit.

3. The combination of a car wheel boring mill having a vertical boring bar and a rotary chuck having a circular series of radially movable clamping jaws, a holding ring adapted to be clamped by the jaws and thereby hold the jaws in concentric relation to the boring bar axis, a grinding mechanism for successively grinding the faces of the jaws as they are rotated by said chuck and comprising a supporting arm detachably mounted on the boring bar extending horizontally beyond the chuck jaws, a motor driven grinding wheel unit carried by said arm, and means for bodily shifting the motor driven grinding unit on said arm to position the grinding wheel in any angular grinding relation to the faces of the jaws.

4. In a car wheel boring mill having a vertical boring bar and a rotary chuck having a circular series of radially movable clamping jaws, a holding ring adapted to be clamped by the jaws and thereby hold the jaws in concentric 7 relation to the boring bar axis, and a supporting arm detachably mounted on the boring bar extending horizontally beyond the chuck jaws, the combination of a motor driven grinding Wheel unit carried by said arm for successively grinding the faces of the jaws as they are rotated by said chuck, means for bodily shifting'the motor driven grinding unit on said arm to position the grinding wheel in any angular grinding relation to the faces of the jaws, and a grinding wheel dressing device mounted on said arm to overlie the grinding wheel when said grinding wheel is moved angulariy to engage the Wheel dressing device.

HENRY IRWIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Certificate of Correction Patent N o. 2,458,472. January 4, 1949 HENRY IRWIN It is hereby certified that errors appear in the printed specification of the above numbered patent requiring correction as follows:

Column 3, line 73, for the Word adjustment read adjusting; column 6, line 49, for monuting read mounting; and that the said Letters Patent should be read With these corrections therein that the same may conform to the record of the ease in the Patent Ofi-ice.

Signed and sealed this 10th day of May, A. D. 1949.

THOMAS F. MURPHY,

Assistant Uommz'sszoner of Patents. 

